That's Goodhart's law, by the way. "When a measure becomes a target, it ceases to be a good measure." Because people game it. https://en.wikipedia.org/wiki/Goo

That's Goodhart's law, by the way. "When a measure becomes a target, it ceases to be a good measure." Because people game it. https://en.wikipedia.org/wiki/Goodhart%27s_law https://en.wikipedia.org/wiki/Goodhart%27s_law There's a related memorable, though probably untrue, anecdote about a Soviet nail factory: https://skeptics.stackexchange.com/questions/22375/did-a-soviet-nail-factory-produce-useless-nails-to-improve-metrics https://skeptics.stackexchange.com/questions/22375/did-a-sov...